Take-up device for sander-drums.



H. I. MITCHELL.

TAKE-UP DEVICE FOR SANDER DRUMS.

APPLICATION FILED OCT- 6. l9l5.

Patented June 27, 1916.

following is a specification.

A grindin U ITE STAT-Es PATENT. OFFICE naamson J. MITCHELL, or BELOIT, WISCONSIN, asst anon To 2. Yams MACHINE comm, or. BE oI'r, wrsconsm, aconroaa'rronorwlsconsm.

TAKE-UP DEVICE 'ron, smnnrnnums. 7

To all 'u z ho'ni'z't may concern:

Be it known that I, HARRISON J. MITCHELL, a citizen ofthe Unitedastates,

Up Devices for Sander-Drums, of which his common in, he abrading cylinder or sander drum appliances for smoothly finishv ing wood, and possibly other materials, to

provide a cylinder on which the sheet of sandpaper or other abrading material is spirally or helically wound, and to associate with such cylinder end' clampingrings or disks to which the terminalportions ofthe abrading sheet are'secured. It has also been customary to provide suchdevices with means for manually adjustingor shifting such end members or disks, either simultaneously or independently, for taking up the slack in the abrading sheet to cause thelatter to-snugly and smoothly fit the surface of the cylinder; 1 Types .or samples of' such-appliances have been fully set forth in United States Patents Nos. 577,582 Lane and Mitchell,- abrading cylinder, granted February 27, 1897., and 1,030,897, Lane, abrading' cylinder, issued July 2, 1912.

One of the leading objects of this invention is to provide an abrading, polishing, or cylinder or drum of this general 7 form with means which will automatically sheet during take up the fullness present in, or which is likely to develop in thespiraL abradant A further eature of the invention resides in the construction of parts in such a manner that the end clamping disk may b'e-i come displaced slightly out of its normal plane to accommodate itself more readily to the unequal loosencss or slack present in the sandpaper. v

In order that those skilled inthis art may have a full-and completeunderstanding of this invention, the structural characteristics and functional advantages of an appliance embodying the. invention, and the manner in which the above-specified'and other objects may be attained, I have illustrated a preferred embodiment of this invention in the accompanying drawing, throughout the vaters refer to the same parts, and which residing at Beloit, in thcounty-ofg-Rock and State of Wisconsm,have invented cer- 'tain new and useful Improvements in Takethe V sreificationofletterslfatilt. Patented June 2'7, 1916.

a lication filed October e,is1s. Serial 1%. 54,316. i

' drawing reference shouldbe hadin connection with the following detailed description of the apparatus.

In this drawing: Figure I is a fragmentarysectional view of such an abradant cyllnder ordrum with its cushion and the covering-sheet of'sandpaper omitted, and with the means forfclamping the ends of such sheet to the end disks omitted; Fig- 2 is a cross-section on line 2 2 of Fig. 1 with the parts viewed in the direction'indicated by the arrows; Fig. 3 is an .enlarged fragment of Fig. 1;,Fig. 4 illustrates one of the pin and diagonally-disposed slot arrangements which translates the longitudinal" movement of each of the end into a spiral movement; Fig. 5.showsinperspec tive one of the operating pinions, and F ig. ectlve a fragment of i 6 also indicates in .pc

the operating-shaft an its'clutch orratchet member.' T I The metal cylinder or drum is composed of. asuitable number of alined sections or parts 10, 11, and 12, the two end ones inthe acterized 10 and 12 respedively Eachof these sectionshas a cylindrical shell 13 which 1s centrally connected by a web 14 to an apertured hub 15, allof these sections being driven or fixed on a main-shaft 16,

which supports them in proper register and alinement. At each end, this compound or built-up cylinder or drum is equipped with fdevice illustrated in the being chari The ends of the strip of sandpaper spirally wound on the drum or cylinder are fastened to these disks by themeans in the patents referred to, or in any other suitable -manner, which fastening elements, however, for the sake of clearness of illus tration, have been omitted from the present drawing. A

The cylindrical hub of the end cylinder section 12 has the hub 19 of a gear 20 rotatably mounted thereon, longitudinal placement of the gear being prevented by the shoulder 21 of the web and the head of a screw 22. The portion of the hub 19 extending outwardly beyond the'end of hub right-hand threaded of end-disk 18.

The webs of the various cylinder sections 7 are apertured in-alinement for the reception I? of an operating shaft 23 parallel to the main shaft 16 and equipped at one end with a pinion 24, theteeth of which are in mesh.

with those of the gear 20. The opposite end portion of the hub 22 'inder or drum has been provided with its of this shaftis squared at 25 for the application of a turning wrench or handle. It is also threaded. at 26 for a portion of its length and beyond the threaded part it has fastened thereto by a pin 27 a collar or clutch member 28 having a tooth .or ratchet portion 29. An' internally-threaded pinion 30 is screwed on to the part 26'of the shaft, its tooth or projection 31 being, adapted to bear against and coiiperate with the tooth 29. The opposite end of this pinion 30 has a sleeve,or shell portion 32 with a pair of slots 33- adapted to co-act with an appropriately-shaped wrench or handle.

paper has been's pirallywound thereon and pinion 30 by reason of the clutch conneccushion covering of felt or, the like; and that the stripof abradant material or sand- 75 fastened to the end members 17 and 18, the' operator by means of a handle applied to] the angular portion of the shaft .23, turns such shaft, rotating the pinion 24 and the 80 tion 29,; 31. Such rotationof these pinions revolves the gears 20, and 35. This move- I ment of the gear 20 causes an outward feed-.

hand screw connection between the parts 19 ing of the disk 18 by reason of the right- 2' 85 and 22 and the disk is at' the same' time As is illustrated in Figs. 1 and 3, the end disk 17 has an aperture at; 34 opposite the ofthe wrenches or 'handles. referred to." Pinion meshes with the teeth of a gear 35, the hub 36 pf which is revolubly mounted on the hub of the cylinder section 10 and bears against a shoulder 37 of the --web of; such section against which it vis held by the" head of a screw 37. The part of thejihub u of gear extending outwardly be 0nd the hub of section 10 is provided interna ly with 35' a left-hand screw-thread which coiiperates ,With and receives the correspondingly threaded hub 38 of an intermediate disk 39, the latter" beingequipped' with four round perforations 4( .each of which 'has fixed 40' therein ashell-or cup 41 projecting inwardly I toward the gear and having an open mouth facingthe end disk 17. Such disk has four pins'or rods 42, 42, fixed thereto,'each in registerwith and accommodated in-the center done of the shells 41 projecting through the aperture 43 in the end-wall of the shell and 'havinga tapered head 44, the shank of su'chpin or rod-being somewhat 'less'i'n diameter than that of the hole 43.- Each of these shells houses a coil expansion spring 45' which at one end bearsagainst the inner face of the disk 17, its other end bearing against the'bottomor end-wall of shell 41.

'As is clearly shown in Fig. 3, thehub'46 of disk. 17 is-recessed at 47 so as to have a comparatively nar'row' ring portionw48 'bear-.

ing on the shaft 16, thus permitting this end,

7 to rock slightly-on the shaft outofits A true or normal planeat right-angles thereto. Each of the end disks 17 and 18 has an internally-projecting' lug 49 supplied with a diagonally-disposed slot 50 accommodating a pm 51 extending inwardly from the shell portion of the corresponding end section of 05 the cylinder. The slots 50 at the two ends shaft 23 to permit the introduction of either oppositeofthat given to the disk 18. This caused to turnangularly on the shaft 16 because of its 'spir'al connection 50, 51 withthe Such spiral or helicalmovement' of the part 18 causes the latter to "take up theslack or remove fullness from the abradant paper. The turning of gear 35 causes. the outward travel of the intermediatedisk39 because of the left-hand screw connection between the parts 36 and 38, and when this member 39 is advanced sufliciently to engage the disk 17, the" studs 42 projecting inwardly through the bottoms of the shells 41,: it car-i ries the disk 17 along with it, and, by reason of the spiral slot and pin connection '50, 51, of the disk with the cylinder-section 10, the two parts 17 and 39- are caused to, turn angularly as they tra'vel axially, that is to say, they will both have aspiral movement the ios action of the disk 17 tightens the sandpaper strip, alsoremoving fullness orslack. Be- 1 fore the member ga n its axial; ouiv'ard tra vel engages the disk 17 the latter may e r sqmewh p m y'fi the expandin'gaction-of-the springs 45-. r

Under ordinary soon after the covered cylinder-is pnt'tolwork a 'loose-.

ness willfdevelop inthe endportion of the abradant' shee secured to the 15 the shoulder 29. turning of the pinion disk 17,, and, it'll order to 6mm such slack 3 without .jdistui-bing the; other disk" 18' to which the, advance end of thc paper is secured, the operatorappliesa'sui bly-sh'aped wrenchor hand-1e to theipart's 3 33of-theq'zo inion 30i'and the latter Ton the "shaft v..3"without revolvin the shaft-itselfl'snclr partial rotation" ofrt 'e pinion carrying, the

tooth'or shoulder 31 forwardly away-from and the intermeshing gear 35 advancesthe parts 39 and-'17 spirally somewhat farther to eliminate the slack referred to; Du the action of. the, cylinder in service, 2, still further slack or looseness in the paper may develop at the end of the cylinder, and this will be automatically taken up by the outward pressingaction of the springs 45 which force the disk 17 axially along the .shaft and as it moves in this direct-ion, it is 3 reason of the looseness of the fit of the studs 42 inthe apertures 43,-or the part 39 may travel with the part- 17, being carried around due to the propelling action of the studs 42. When the elements referred \to are brought back to theirinitial positions for the replacing of a worn sandpaper sheet with a new one, the conical heads 44 of the pins 42 will act to center or register the members 39 and 17 relatively to one another, all as will be readily understood. c

It is, of course, difiicult, if not impossible; to Wrap the sheet of abradant material spirally around the cylinder and have the looseness or slack exactly uniformly distributed around the periphery of the cylinder at its end. It is, therefore, desirable to so construct the take-up device that it can adjust itself to such irregularities and in the present appliances this is accomplished by making th bearing of the disk 17 on the shaft 16 so-narrow that the disk can turn slightly obliquely to the shaft, which wilhautomatically occur under the action of the springs 45. 'That is to say, where the slack is greatest, the disk will be freer to rock and such shifting out of its normal right-angle position will be brought about by the expanding action of the-springs atthose points. As

will be readily understood the looseness of fit of the rods 42 in the apertures 43 permits this action to occur without binding of the associated parts.

Although I have herein illustrated and described ,a preferred embodiment of the invention somewhat in detail, it is to be re-' membered that the invention is susceptible of a variety of embodiments and that many 'minor mechanical changes may be made int the structure illustrated without departure from the substance of the invention.

I claim: 1, In an abrading-appliance, the combinatlon of a cylinder whose surface is adapted to be spirally covered with a sheet of,

abrading material, a clamping member at an end of the cylinder, means to fasten the abrading materlal to said member, and

means toautomatically shift said member spirally relatively to the cylinder to take up slack in said abrading material, substantially as described.

clamping member and extending 2. In an abrading-appliance, the combination of a cylinder whose surface is adapted to be spirally covered with a sheet of abrading material, a clamping member at an end of the cylinder, means to fasten the abrading material to said member, and spring-actuated means to automatically shift said member spirally relatively to the cylinder to take up slack in said abrading material, substantially as described.

3. In an abrading-appliance, the combination of a cylinder whose surface is adapted to be spirally covered with a sheet of abrading material, a clamping member at an end of the cylinder, means to fasten the abrading material to said member, manually-operated means to shift said member spirally to take up slack in said abrading material, and means to automatically shift said member spirally to take up slack in said material, substantially as described.

4. In an abrading-appliance, the combination of a cylinder whose surface is adapted to be spirally covered with a sheet of abrading material to said member, screwthreaded means to shift said member longitudinally of the cylinder, spring-means tending to automatically move said member longitudinally-of the cylinder, andmeans to translate such longitudinal movement of the member, into a spiral movement, substantially asldescribed.

5. In an abrading-appliance, the combination of acyli der whose surface is adapted to be spirally covered with a sheet of abrading material, a clamping member at an end of the cylinder, means to fasten the abrading material-to said member, screwthreaded means tb shift said member longi tudinally of the cylinder, spring-means interposed between said screw-threaded means and said member to automatically move said member longitudinally of the cylinder, and means to translate such longitudinal movement into a spiral movement, substantially as describedq 6. In an abrading-applia ce, the combination of a cylinder whose sur ace is adapted to be spirally covered with a sheet of abrading-material, a clamping member at an end of the cylinder, means to fastenxthe abrading-material to said member, an intermediate member provided witha plurality of ough said sockets, springs in said sockets be ring against said clamping member, screwthreaded means to move said clamping and apertured sockets, pins fastenedxgigsaid intermediate member's longitudinally of the cylinder, and means to translate such lon gitudinal movement of the clamping-memher into a spiral movement thereof, substantially as described.

material to said clamping member, and

is mounted, a clamping-member at an end of,

said cylinder constructed to permit it to shift into a plane slightly oblique to he axis of the shaft, means to secure the a radlng means pressing outwardly on said member tending to shift it into an oblique position to compensate for the inequality in the slack in the abrading material, substantially as described.

" 8. In an abrading-appliance, the combina tion of a cylinder whose surface is adapted to be spirally covered with a sheet of abrading material, a shaft on which said cylinder is mounted, a clamping-member at an end of said cylinder having a sufiiciently narrow bearing on said shaft to permit it to shift into a plane slightly oblique to the axis of the shaft, means to secure the abradingequality in the slack in the abrading ma- T terial, substantially as described.

9. In an abradmg-appliance, the combi nation of a cylinder whose surface is adapted to be spirally covered witha sheet of abrading material, a clamping member at an end of the c linder, means to fasten the abrading material to said member, an intermediate member, a loose connection between said clamping and intermediate members,

means tending to center said clamping and intermediate members relatively to one another, screw-threaded means to move said clamping and intermediate members longitudinally of the cylinder, and means to translate such longitudinal movement of the clamping member into a spiral movement, substantially as described.

HARRISON J. MITCHELL. 

